Method for imparting to drying means a large superficial area



' hydrate andv Patented June 28,1927.

"UNITED STATES PATENT OFFICE.

EDUARD SMOLGZYK, OF IBIESDOBF-SUD, NEAB BERLIN, GERMANY.

METHOD FOR HIIPARTING TO DRYING MEANS LARGE SUPEBFICIAL AREA.

K Drawing.

'As experience has shown drying agents a will act the more intensivelythe larger the area of the surface offered to the substance to be dried.A means for obtaining such large surface consists in depositing thedrying agent upon a carrier having large superficial -areas, as forinstance pumice, glass wool and so on. In many instances this way oftreatment did not prove practicable since the drying agent did not stickto the carrier. em-

ployed.

According to the invention adhesion is obtained inth s instance in thata small portion of the dryin agent is transferred to its that thecarrier employed is impregnated at first with such hydrate and thenbrought into contact with the unchanged drying agent. In this manner itis possible to deposit for instance pentoxide of phosphorus upon pumice,to which it. will not adhere otherwise, by impregnating the pumice in anappropriate manner with metaphosphoric acid, and then the whole mass isagitated in an excess of pentoxide of phosphorus until all the pentoxideof phosphorus will stick to the previously treated grains of pumice. Ithas been found, that it will suffice to deposit about one fifth of thequantity of pentoxide of phosphorus used in the form Application filedJune 8,1926, Serial No. 113,588, andin Germany June 8, 1925.

of meta-phosphoric acid in order to obtain 30 adhesion of the remainingfour fifths thereof. 'During the operation meta-phosphoric acid will beformed from the pentoxide of phosphorus, which acid will penetrate intothe interior of the grains of pumice, causing 85 the surface of thegrains to become free for reception of additional quantities ofpentoxide of phosphorus. Thus the granular material employed can beimpregnated repeatedly with drying agents. 40

A further advantage in employing drying agents ofthe kind referred toabove is to be seen in the fact, that while the drying agent per so onaccount of its physical properties could only flow over the substance tobe dried, it is now possible to fill it in drying towers and the likeandcause ages to be dried, to flow through the column, admitting of a moreintensive and rapid drying operation.

I claim:

Method for'imparting to drying means a large superficial area comprisingdepositing said means upon a porous carrier, and cmloying as binderbetween the carrier and the 66 rying agent a hydrate of the latter.

In testimony whereof I aflix my signature.

Dn. PHIL. EDUARD SMOLCZYK.

